Katy Perry is "continuing to move forward" amid a turbulent year in her personal life.

On Monday, the popstar took to Instagram to mark the first anniversary of her seventh studio album, 143.

Alongside a slideshow of snaps and videos taken over the course of her The Lifetimes Tour performances, Katy shared a candid letter addressed to her fans.

"You KCs (KatyCats) know I'm not one for anniversary posts. I tend to be mostly a futurist but it would be negligent of me to not acknowledge the incredible impact this last year has had on me," she began. "Records are snapshots of an artist trying to tell their story of where they are now or have been, and hope someone will hear themselves in some of the messages. 143 to me was literally me saying I love you to my fans."

Katy went on to emphasise how proud she is of her "community" and seemingly referred to the negative reviews of 143 from music critics.

"History is important, we learn from history, we are reminded of how to and what not to do when we look back. We celebrate the wins and reflect on the losses. All of it is valuable. Let's hope we get to evolve together for years to come and at the end of it all be proud and at peace with how we tried our best in this imperfect world," the 40-year-old continued.

Elsewhere in the heartfelt message, Katy appeared to allude to the changes in her personal life too.

In July, the Firework hitmaker and partner Orlando Bloom officially announced they had split after nine years together. The pair share a five-year-old daughter named Daisy.

"Whatever comes next, I'm letting it unfold naturally. No forcing, no controlling - just trusting the angels, the fans, and the music to guide me where I'm meant to go. Please know this: my love for you is unconditional, and I couldn't do any of this without you," she enthused.

To conclude the emotional post, Katy recalled how a friend once gifted her a framed copy of the 1886 children's book, What Katy Did Next.

"I've never read it, but the title has always stuck with me. That's the point - it's about continuing to move forward, and dream," the Roar star added.

Katy is next scheduled to perform in Belfast, Northern Ireland on 4 October.